As the conventional techniques relating to the present invention, an automatic disk exchange apparatus will now be described by way of example. This type of automatic disk exchange apparatus is designed for use as a peripheral equipment for optical information reproducing apparatus and it is disclosed for example in Laid-Open Patent No. 60-243865.
FIG. 14 is a perspective view showing a conventional automatic disk exchange apparatus. In the Figure, numeral 1 designates disk cartridges each containing an optical disk, 2 disk storage devices each in the form of a bookcase having a plurality of slots for vertically storing the disk cartridges 1,3 drive units for recording onto and reproducing information from the optical disks, 4 a transport device arranged in opposition to the disk inlet/outlet ports of the storage devices 2, 5 a transport frame supported in a cantilevered manner on a rotating part 4a of the transport device 4, the transport frame 5 incorporating transfer means for transferring the disk cartridge 1.
With the automatic disk exchange apparatus constructed as described above, in order to transport selected one of the disk cartridges 1 stored in the storage device 2 to the drive unit 3 for information recording/reproducing purposes, the transport device 4 is driven into operation so that the transport frame 5 as moved in an X direction or the traverse direction, and a Z direction or the vertical direction, thereby stopping it at the position where the selected disk cartridge 1 is stored. In this condition, the given disk cartridge 1 is moved in the Y direction by the transfer means of the transport frame 5 to transfer it from the storage device 2 to the transport frame 5.
Then, after the transport frame 5 has been rotated through 90 degrees by the rotating means 4a of the transport device 4 thereby bringing it into a horizontal position, the transport frame 5 is moved downward, transported to the position of the drive unit 3 and stopped thereat by means of the transport device 4. Thereafter, the disk cartridge 1 in the transpoint frame 5 is inserted through an inlet/outlet port 6 of the drive unit 3 and mounted in position within the drive unit 3. When the disk cartridge 1 is mounted in the drive unit 3, its optical disk is subjected to the recording/reproduction of information by the drive unit 3.
When the recording/reproduction by the drive unit 3 is completed, the disk cartridge 1 is delivered to the transport frame 5 from the drive unit 3. The transport frame 5 is transported in the reverse direction to the previously mentioned operation and the disk cartridge 1 is restored in the initial position in the storage device 2.
Also, when selected one of the disk cartridges 1 stored in the storage device 2 is to be removed to the outside for changing, the disk cartridge 1 to be changed is temporarily stored in a vacant slot 7 provided in the storage device 2 by the transport unit 4. This disk cartridge 1 is removed to the outside through a cartridge inlet/outlet port 8. When a disk cartridge 1 is to be stored in the storage device 2 from the outside, the disk cartridge 1 is inserted through the cartridge inlet/outlet port 8, and the disk cartridge 1 stored in the vacant slot 7 is removed, transported to a given position in the storage device 2 and stored thereat by the transport device 4.
In this way, it is possible to store a plurality of disk cartridge 1 in the storage devices 2 and automatically transport the stored disk cartridges 1 between the storage devices 2 and the drive units 3, thereby affecting the recording and reproduction of information efficiently.
In accordance with the above-described conventional automatic disk exchange apparatus, however, in view of the fact that the disk cartridges 1 are vertically stored in the storage device 2 and the drive unit 3 is arranged horizontally, the transportation between the storage device 2 and the drive unit 3 requires that the transport frame 5 is caused to make not only a three-dimensional motion in the X, Y and Z directions but also a rotary motion for changing the position of the disk cartridge. As a result, there are drawbacks that the transport device 4 is complicated in construction and that troubles tend to occur easily.
Also, since the transport frame 5 is required to make a three-dimensional motion and a rotary motion, as for example, the three-dimensional motion for moving the transport fame 5 requires 3 to 4 seconds and the rotary motion requires about 1 second, thus requiring about 4 to 5 seconds as the total access time. If the disk cartridges 1 are stored at a place more remote from the drive unit 3, this access time is additionally increased correspondingly. Thus, there is also a disadvantage that the time interval between the removal of the disk cartridge 1 from the storage device 2 and the mounting of it in the drive unit 3 is increased.
There is another disadvantage that since the transport frame 5 is supported in a cantilevered manner on the transport device 4, not only the transport frame 5 must be balanced by balancing means such as springs but also a motor producing a large torque is required for rotating the transport frame 5 against the force of the balancing means, thereby further complicating the construction and increasing the failure rate and the production cost.
Further, since the storage device 2 is arranged along the transport path of the transport frame 5 which is supported in a cantilevered manner on the transport device 4, the storage device 2 can be provided only on one side of the transport frame 5 and therefore there are disadvantages that the accommodation efficiency of the disk cartridges 1 is deteriorated and that the apparatus is inevitably increased in size in cases where a large number of disk cartridges 1 are accommodated.
Further, where the disk cartridges 1 are to be changed between the outside and the storage devices 2, the exchange is effected by removing and introducing the disk cartridges 1 through the cartridge inlet/outlet port 8 always one at a time and thus there is the disadvantage that much time is required for storing and returning a plurality of the disk cartridges 1.